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To achieve full solar spectrum absorption of organic dyes for organic solar cells and organic solar antenna collectors, a series of tetraanthracenylporphyrin derivatives including H2(TAnP), H2(α-F4TAnP), H2( β,β'-F8TAnP), H2(γ,γ'-F8TAnP), H2(δ,δ'-F8TAnP), H2[α-(NH2)4TAnP], H2[β,β'-(NH2)8TAnP], H2[γ,γ'-(NH2)8TAnP], and H2[δ,δ'-(NH2)8TAnP] was designed and their electronic absorption spectra were systematically studied on the basis of TDDFT calculations. The nature of the broad and intense electronic absorptions of H2(TAnP) in the range of 500-1700 nm is clearly revealed, and different types of π → π* electronic transitions associated with different absorption bands are revealed to correspond to different electron density moving direction between peripherally fused 14-electron-π-conjugated anthracene units and the central 18-electron-π-conjugated porphyrin core. Introduction of electron-donating groups onto the periphery of the H2(TAnP) macrocycle is revealed to be able to lead to novel NIR dyes such as H2[α-(NH2)4TAnP] and H2[δ,δ'-(NH2)8TAnP] with regulated UV-vis-NIR absorption bands covering the full solar spectrum in the range of 300-2400 nm. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were carried out to comparatively study the molecular structures, atomic charges, molecular orbitals, and electronic absorption spectra of fluoroboron−subtriazaporphyrin (SubTAP) and fluoroboron−subphthalocyanine (SubPc) as well as their benzo-fused low-symmetrical derivatives AaBbCc(3 ≥ a, b, c≥ 0). The peripherally fused benzene rings are revealed to have a significant effect on the structure and charge density distribution of the inner nitrogen atoms of subtriazaporphyrin core, while the charge of the central fluoroboron group changes very little. The effect of peripherally fused benzene rings on the frontier molecular orbitals of different compounds is comparatively discussed. The nature of the electron excitation between the frontier molecular orbitals of the 20 compounds is assigned according to the calculation results. The benzene rings fused directly onto pyrrole rings have been revealed to show more effect on the inner nitrogen atom than the outer benzene rings fused onto the periphery of isoindole rings. The present work will be helpful toward systematically understanding the effect of ring enlargement through asymmetrically fusing benzene ring(s) onto the subtriazaporphyrin skeleton on the structures and properties of fluoroboron−subtriazaporphyrin and fluoroboron−subphthalocyanine analogues. [ABSTRACT FROM AUTHOR]